An idea came to me to see if a simple wood gasifier could be made to run a small engine. Many folks get on the wood gas forums and want to use wood gas, but aside from buying a GEK, Woody or delve into a BIG DYI project, there is no easy way. Warning, I have only run this unit twice so it needs more run time, but I think it is worth investing some R&D. It is an easy way for some one who is serious about wood gas to get an engine running.
The reactor is made from a steel pail that holds about 4 gallons. If the pail were bigger, the engine would run longer. The air inlet is made from a 3/4" nipple welded to a 16 guage piece of sheet metal. This sheet metal is curved to fit the contour of the pail and is held in place with four #10 screws. This means it can be removed and put on another pail when the pail goes bad. Be sure to use some red RTV silicone to make an air tight seal between the plate and the pail.
There is a pipe flange that bolts to the lid of the pail. Once again use high temp RTV silicone to seal off any air. The long iron pipe from the lid of the reactor is to cool the gas before it enters in the plastic sump pump hose. As long as the charcoal bed is sufficient in depth, the gas outlet pipe stays well within 120F. When the charcoal bed gets too low, excess heat is allowed to escape and the pipe gets hot. This took 30 minutes on this unit. A deeper charcoal bed will allow you to run longer. The gas runs through a legnth of hose and into a filter. This is a simple tin can with a tight fitting lid. Once again, pipe flanges are used to connect the pipe to the sheet metal. Simple open cell foam is used to trap any charcoal dust that comes through. It is a dry filter. Wood gas is mixed with air via a 3/4" gate valve before going into the carburator. This gate valve is used to get the right air/woodgas ratio and is adjusted by listening to the sound of the engine. Once set, it rarely gets moved. Some of the exhaust gas is recycled into the reactor. This helps cool the reaction, adds more carbon thus decreasing the amount of charcoal used, and adds water vapor that is cracked into hydrogen. The amount of exhaust entering the reactor is controlled by another gate valve. I set this by eye. Looking for a bright cherry red reaction. Too much exhaust and the reaction is too cool, too little exhaust and the nozzle melts.
To run this unit, you do need to burn charcoal. Not briquits, but natural lump charcoal that has been graded by passing through a 3/4" screen and stopped by a 1/8" screen. I’d say there is 3 hours in modifying the exhaust and carburtor to accept the pipe fittings. Also includes the time to modify the pail make the nozzle and install the pipe flanges.
Any of you guys want to give it a try and see how it works for you? Ray had a bunch of questions that I’ll address on his post.
Until later, Gary in PA